4/9 pubmed: "regenerative medici...

Please add updates@feedmyinbox.com to your address book to make sure you receive these messages in the future. pubmed: "regenerative medici... Stem Cells - SMi's Second Annual Conference - Achieving success in science and commercialisation. April 8, 2010 at 6:27 AM Stem Cells - SMi's Second Annual Conference - Achieving success in science and commercialisation. IDrugs. 2010 Apr;13(4):232-4 Authors: Lucifero D SMi's second annual Stem Cells conference, held in London, included topics covering research developments in the field of stem cell biology and regenerative medicine. This conference report highlights selected presentations on big pharma's perspective on the field, stem cell-based therapies for chronic liver disease and age-related macular degeneration, and strategies to gain approval for the conduct of clinical trials involving stem cells. Investigational drugs discussed include GRNOPC-1 (Geron Corp). PMID: 20373250 [PubMed - in process]   Albumin and mammalian cell culture: implications for biotechnology applications. April 8, 2010 at 6:27 AM Albumin and mammalian cell culture: implications for biotechnology applications. Cytotechnology. 2010 Apr 6; Authors: Francis GL Albumin has a long historical involvement in design of media for the successful culture of mammalian cells, in both the research and commercial fields. The potential application of albumins, bovine or human serum albumin, for cell culture is a by-product of the physico-chemical, biochemical and cell-specific properties of the molecule. In this review an analysis of these features of albumin leads to a consideration of the extracellular and intracellular actions of the molecule, and importantly the role of its interactions with numerous ligands or bioactive factors that influence the growth of cells in culture: these include hormones, growth factors, lipids, amino acids, metal ions, reactive oxygen and nitrogen species to name a few. The interaction of albumin with the cell in relation to these co-factors has a potential impact on metabolic and biosynthetic activity, cell proliferation and survival. Application of this knowledge to improve the performance in manufa! cturing biotechnology and in the emerging uses of cell culture for tissue engineering and stem cell derived therapies is an important prospect. PMID: 20373019 [PubMed - as supplied by publisher]   Preparation of a novel biodegradable nanocomposite scaffold based on poly (3-hydroxybutyrate)/bioglass nanoparticles for bone tissue engineering. April 8, 2010 at 6:27 AM Preparation of a novel biodegradable nanocomposite scaffold based on poly (3-hydroxybutyrate)/bioglass nanoparticles for bone tissue engineering. J Mater Sci Mater Med. 2010 Apr 7; Authors: Hajiali H, Karbasi S, Hosseinalipour M, Rezaie HR One of the most important challenges in composite scaffolds is pore architecture. In this study, poly (3-hydroxybutyrate) with 10% bioglass nanoparticles was prepared by the salt leaching processing technique, as a nanocomposite scaffold. The scaffolds were characterized by SEM, FTIR and DTA. The SEM images demonstrated uniformed porosities of appropriate sizes (about 250-300 mum) which are interconnected. Furthermore, higher magnification SEM images showed that the scaffold possesses less agglomeration and has rough surfaces that may improve cell attachment. In addition, the FTIR and DTA results showed favorable interaction between polymer and bioglass nanoparticles which improved interfaces in the samples. Moreover, the porosity of the scaffold was assessed, and the results demonstrated that the scaffold has uniform and high porosity in its structure (about 84%). Finally it can be concluded that this scaffold has acceptable porosity and morphologic character pav! ing the way for further studies to be conducted from the perspective of bone tissue engineering. PMID: 20372984 [PubMed - as supplied by publisher]   Comparison of contractile behavior of native murine ventricular tissue and cardiomyocytes derived from embryonic or induced pluripotent stem cells. April 8, 2010 at 6:27 AM Comparison of contractile behavior of native murine ventricular tissue and cardiomyocytes derived from embryonic or induced pluripotent stem cells. FASEB J. 2010 Apr 6; Authors: Xi J, Khalil M, Shishechian N, Hannes T, Pfannkuche K, Liang H, Fatima A, Haustein M, Suhr F, Bloch W, Reppel M, Saric T, Wernig M, Jänisch R, Brockmeier K, Hescheler J, Pillekamp F Cardiomyocytes generated from embryonic stem cells (ESCs) and induced pluripotent stem (iPS) cells are suggested for repopulation of destroyed myocardium. Because contractile properties are crucial for functional regeneration, we compared cardiomyocytes differentiated from ES cells (ESC-CMs) and iPS cells (iPS-CMs). Native myocardium served as control. Murine ESCs or iPS cells were differentiated 11 d in vitro and cocultured 5-7 d with irreversibly injured myocardial tissue slices. Vital embryonic ventricular tissue slices of similar age served for comparison. Force-frequency relationship (FFR), effects of Ca(2+), Ni(2+), nifedipine, ryanodine, beta-adrenergic, and muscarinic modulation were studied during loaded contractions. FFR was negative for ESC-CMs and iPS-CMs. FFR was positive for embryonic tissue and turned negative after treatment with ryanodine. In all groups, force of contraction and relaxation time increased with the concentration of Ca(2+) and decrea! sed with nifedipine. Force was reduced by Ni(2+). Isoproterenol (1 muM) increased the force most pronounced in embryonic tissue (207+/-31%, n=7; ESC-CMs: 123+/-5%, n=4; iPS-CMs: 120+/-4%, n=8). EC50 values were similar. Contractile properties of iPS-CMs and ESC-CMs were similar, but they were significantly different from ventricular tissue of comparable age. The results indicate immaturity of the sarcoplasmic reticulum and the beta-adrenergic response of iPS-CMs and ESC-CMs.-Xi, J., Khalil, M., Shishechian, N., Hannes, T., Pfannkuche, K., Liang, H., Fatima, A., Haustein, M., Suhr, F., Bloch, W., Reppel, M., Sarić, T., Wernig, M., Jaenisch, R., Brockmeier, K., Hescheler, J., Pillekamp, F. Comparison of contractile behavior of native murine ventricular tissue and cardiomyocytes derived from embryonic or induced pluripotent stem cells. PMID: 20371616 [PubMed - as supplied by publisher]   The interaction of cells and bacteria with surfaces structured at the nanometer scale. April 8, 2010 at 6:27 AM The interaction of cells and bacteria with surfaces structured at the nanometer scale. Acta Biomater. 2010 Apr 3; Authors: Anselme K, Davidson P, Popa AM, Giazzon M, Liley M, Ploux L The current development of nanobiotechnologies requires a better understanding of the cell-surface interactions at the nano-scale. Recently, advances in nanoscale patterning and detection have allowed the fabrication of appropriate substrates and the study of cell-substrate interactions. In this review we discuss the methods currently available for nanoscale patterning and their merits, as well as techniques for controlling the surface chemistry of materials at the nanoscale without changing nanotopography, and the possibility of truly characterizing the surface chemistry at the nanoscale. We then discuss the current knowledge of how a cell can interact with a substrate at the nanoscale and the effect of size, morphology, organization and separation of nanofeatures on cell response. Moreover, cell-substrate interactions are mediated by the presence of proteins adsorbed from biological fluid on the substrate. Many questions remain on the effect of nanotopography on! protein adsorption. We review the papers related to this point. As all these parameters have an influence on cell response, it is important to develop specific studies to point out their relative influence as well as the biological mechanisms underlying the cell response to nanotopography. This will be the basis for future research in this field. An important topic to tissue engineering is the effect of nanoscale topography on bacteria, since cells have to compete with bacteria in many environments. The limited current knowledge on this topic is also discussed in view of using topography to encourage cell adhesion while limiting bacterial adhesion. We also discuss current and prospective applications of cell-surface interactions at the nanoscale. Finally, based on the questions described previously that remain to be solved in the field, we propose future directions of research in materials science to help elucidate the relative influence of the physical and chemical aspect! s of nanotopography on bacteria and cell response with the aim! of cont ributing to the development of nanobiotechnologies. PMID: 20371386 [PubMed - as supplied by publisher]   Geometric microenvironment directs cell morphology on topographically patterned hydrogel substrates. April 8, 2010 at 6:27 AM Geometric microenvironment directs cell morphology on topographically patterned hydrogel substrates. Acta Biomater. 2010 Apr 2; Authors: Poellmann MJ, Harrell PA, King WP, Johnson AJ Cell behavior is influenced by numerous factors in the physical environment, and a deep understanding of these interactions can lead to the design of better scaffolds for tissue engineering. In vitro substrates can be used to evaluate a wide range of factors, such as topography, and identify which show promise for further evaluating in vivo. Polyacrylamide hydrogels featuring a combinatorial, micropatterned array of posts with varied shape, width, and spacing were produced using a one-step technique. Substrates were covalently modified with collagen and seeded with D1 ORL UVA mesenchymal stem cells. Patterning was shown to direct several quantitative measures of cell morphology. Cell bodies tended to be located in gaps 15 mum and wider, but on top of posts when gaps were 5 mum and smaller. Cells on substrates with square posts and narrow gaps tended to elongate in the direction of gaps. Finally, smaller gaps on all substrates were also shown to influence the place! ment of cell extensions. The parameters identified may be incorporated into substrates to direct specific aspects of cell morphology. PMID: 20371305 [PubMed - as supplied by publisher]   The effect of topology of chitosan biomaterials on the differentiation and proliferation of neural stem cells. April 8, 2010 at 6:27 AM The effect of topology of chitosan biomaterials on the differentiation and proliferation of neural stem cells. Acta Biomater. 2010 Apr 2; Authors: Wang G, Ao Q, Gong K, Wang A, Zheng L, Gong Y, Zhang X Neural stem cells (NSCs) are capable of self-renewal and differentiating into three principle central nervous system (CNS) cell types under the specific local microenvironment. Chitosan films (Chi-F), chitosan porous scaffolds (Chi-PS), and chitosan multimicrotubule conduits (Chi-MC) were used to investigate their effects on the differentiation and proliferation of NSCs isolated from the cortices of fetal rats. In the presence of 10% fetal bovine serum (FBS), most NSCs cultured on Chi-F differentiated into astrocytes, NSCs cultured on Chi-MC showed a significant increase in neuronal differentiation, while Chi-PS somewhat promoted NSCs to differentiate into neurons. However, in serum free medium with 20 ng/ml basic fibroblast growth factor (bFGF), NSCs cultured on Chi-F showed the best proliferation behavior, and NSCs cultured on Chi-MC showed a moderate cell proliferation, but NSCs cultured on Chi-PS exhibited the least cell proliferation behavior. These observati! ons indicate that chitosan topology structure can play an important role in regulating differentiation and proliferation of NSCs and raise the potential utilization of chitosan as various structural biomaterials in neural tissue engineering. PMID: 20371303 [PubMed - as supplied by publisher]   Characterization and In Vitro Cytocompatibility of Piezoelectric Electrospun Scaffolds. April 8, 2010 at 6:27 AM Characterization and In Vitro Cytocompatibility of Piezoelectric Electrospun Scaffolds. Acta Biomater. 2010 Apr 2; Authors: Weber N, Lee YS, Shanmugasundaram S, Jaffe M, Arinzeh TL Previous studies have shown that electrical charges influence cell behavior (e.g., enhancement of nerve regeneration, cell adhesion, cell morphology). Thus, piezoelectric scaffolds might be useful for various tissue engineering applications. Fibrous scaffolds were successfully fabricated from permanent piezoelectric poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) by the electrospinning technique. Scanning electron microscopy (SEM) and capillary flow analyses verified that the fiber mats had an average fiber diameter of 970 +/- 480 nm and a mean pore diameter of 1.7 mum, respectively. Thermally stimulated depolarization current (TSDC) spectroscopy measurements confirmed the piezoelectric property of the PVDF-TrFE fibrous scaffolds by the generation of a spontaneous current with the increase in temperature in the absence of an electric field, which was not detected in the unprocessed PVDF-TrFE powder. Differential scanning calorimetry (DSC), thermogravimetri! c analysis (TGA), X-ray diffraction (XRD), and fourier transform infrared spectroscopy (FTIR) results showed that the electrospinning process increased the crystallinity and presence of the polar, beta-phase crystal as compared to the unprocessed powder. Confocal fluorescence microscopy and a cell proliferation assay demonstrated spreading and increased cell numbers (human skin fibroblasts) over time on PVDF-TrFE scaffolds, which was comparable to tissue culture polystyrene (TCPS). The relative quantity of gene expression for focal adhesion proteins (measured by real-time RT-PCR) increased in the following order: paxillin < vinculin < focal adhesion kinase < talin. However, no differences could be seen among the TCPS surface and the fibrous scaffolds. Future studies will focus on possible applications of this cytocompatible PVDF-TrFE scaffolds in the field of regenerative medicine. PMID: 20371302 [PubMed - as supplied by publisher]   Heterotopic ossification in wartime wounds. April 8, 2010 at 6:27 AM Heterotopic ossification in wartime wounds. J Surg Orthop Adv. 2010;19(1):54-61 Authors: Forsberg JA, Potter BK Heterotopic ossification (HO) refers to the formation of mature lamellar bone in nonosseous tissue. In the setting of high-energy wartime extremity wounds, HO is expected to complicate up to 64% of patients, has a predilection for the residual limbs of amputees, and remains a significant source of disability. Although the inciting events and the definitive cell(s) of origin continue to remain elusive, animal models and human histology samples suggest that HO formation follows a predictable sequence of events culminating in endochondral ossification. Primary prophylaxis is not medically or logistically practical in most cases because patients have generally sustained massive wounds and are undergoing serial debridements during an intercontinental aeromedical evacuation. Surgical excision of symptomatic lesions is warranted only after an appropriate trial of conservative measures and is associated with low recurrence rates in appropriately selected patients. Future ! research regarding prognostication and defining the early molecular biology of ectopic bone may permit individualized prophylaxis and development of novel targeted therapies. PMID: 20371008 [PubMed - in process]   Outcomes of internal fixation in a combat environment. April 8, 2010 at 6:27 AM Outcomes of internal fixation in a combat environment. J Surg Orthop Adv. 2010;19(1):49-53 Authors: Stinner DJ, Keeney JA, Hsu JR, Rush JK, Cho MS, Wenke JC, Ficke JR Due to the nature of the wounds and environment, internal fixation in battlefield treatment facilities is discouraged despite the lack of data. The purpose of this review is to describe the outcomes of fractures that were internally fixed in the combat environment. The records of patients who had internal fixation performed in the theater of combat operations were reviewed. Demographics, injury characteristics, procedure history, and outcomes were recorded and analyzed. Forty-seven patients had internal fixation performed on 50 fractures in a combat theater hospital. Hip, forearm, and ankle fractures made up the majority of cases with 14 (28%), 14 (28%), and 10 (20%), respectively. Sixteen (32%) fractures were open. The average Injury Severity Score was 11.4 +/- 1.1 (range, 4-34). Thirty-nine fractures (78%) healed without incidence. There was one (2%) infection and one (2%) acute surgical complication. Ten (20%) fractures, including the one infection, required ad! ditional procedures. Because internal fixation in the combat environment was used judiciously, complications were not higher than previously reported. PMID: 20371007 [PubMed - in process]   Use of umbilical cord blood for stem cell research. April 8, 2010 at 6:27 AM Use of umbilical cord blood for stem cell research. J Obstet Gynaecol Can. 2010 Jan;32(1):58-61 Authors: Bordet S, Nguyen TM, Knoppers BM, Isasi R Umbilical cord blood (UCB), long treated as waste material, is today considered a valuable source of hematopoietic stem cells. UCB is used, mostly in children, for the treatment of blood malignancies and inherited blood and metabolic disorders. In addition to blood precursor cells, UCB also contains stem cells that can differentiate into other types, such as cartilage, fat, hepatic, cardiac, and neural cells, fuelling speculation about the use of cord blood stem cells for regenerative medicine. Further research is therefore needed to investigate the expanded potential of UCB and its therapeutic use in cell and tissue therapies. According to a recent survey, practices for the procurement of UCB for research vary widely across Canada, so this area may not yet be ready for uniform regulation. However, some harmonization of practices to increase the availability of UCB for research would be useful for Canadian investigators. In this article, we address several importa! nt ethical and legal issues relating to the use of UCB in research and recommend guidelines to serve as a source of useful information for researchers. While their legal acceptability may vary across Canada, it is hoped that these recommendations foster more harmonized UCB research practices. PMID: 20370983 [PubMed - in process]   Nitric oxide, its downstream second messenger cGMP and cAMP enhance adipogenesis in primary human preadipocytes. April 8, 2010 at 6:27 AM Nitric oxide, its downstream second messenger cGMP and cAMP enhance adipogenesis in primary human preadipocytes. Cytotherapy. 2010 Apr 6; Authors: Hemmrich K, Gummersbach C, Paul NE, Goy D, Suschek CV, Kröncke KD, Pallua N Abstract Background aims. Obesity is correlated with chronic low-grade inflammation. Thus the induction of inflammation could be used to stimulate adipose tissue formation in tissue-engineering approaches. As nitric oxide (NO) is a key regulator of inflammation, we investigated the effect of NO and its downstream signaling molecule guanosine 3',5'-cyclic monophosphate (cGMP) as well as adenosine 3',5'-cyclic monophosphate (cAMP) on preadipocytes in vitro. Methods. Preadipocytes were isolated from human subcutaneous adipose tissue, cultured until confluence, and differentiated. The NO donor diethylenetriamine (DETA)/NO (30-150 microm) was added during proliferation and differentiation. Additionally, cGMP/cAMP analogs 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP), 8-(4-chlorophenylthio)-guanosine 3',5'-cyclic monophosphate (8-pCPT-cGMP) and 8-bromoadenosine 3',5'-cyclic monophosphate (8-Br-cAMP), and the adenylyl cyclase activator forskolin, specific guany! lyl cyclase inhibitor 1H-[ 1 , 2 , 4 ]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and adenylyl cyclase inhibitor 2'-5'-dideoxyadenosine (ddA), were applied. Proliferation and differentiation were evaluated. Results. DETA/NO in combination with the standard differentiation procedure significantly enhanced maturation of precursor cells to adipocytes. Proliferation, in contrast, was inhibited in the presence of NO. The application of cGMP and cAMP, respectively, increased pre-adipocyte differentiation to an even higher extent than NO. Inhibitors of the underlying pathways caused a significant decrease in adipogenic conversion. Conclusions. Our results support the application of NO donors during transplantation of preadipocytes in a 3-dimensional setting to accelerate and optimize differentiation. The results suggest that, instead of the rather instable and reactive molecule NO, the application of cGMP and cAMP would be even more effective because these substances have a stronger a! dipogenic effect on preadipocytes and a longer half-life than ! NO. Also , by applying inhibitors of the underlying pathways, the induced inflammatory condition could be regulated to the desired level. PMID: 20370354 [PubMed - as supplied by publisher]   Good manufacturing practice-grade production of unrestricted somatic stem cell from fresh cord blood. April 8, 2010 at 6:27 AM Good manufacturing practice-grade production of unrestricted somatic stem cell from fresh cord blood. Cytotherapy. 2010 May;12(3):338-48 Authors: Aktas M, Buchheiser A, Houben A, Reimann V, Radke T, Jeltsch K, Maier P, Zeller WJ, Kogler G Abstract Background aims. The discovery of unrestricted somatic stem cells (USSC), a non-hematopoietic stem cell population, brought cord blood (CB) to the attention of regenerative medicine for defining more protocols for non-hematopoietic indications. We demonstrate that a reliable and reproducible method for good manufacturing practice (GMP)-conforming generation of USSC is possible that fulfils safety requirements as well as criteria for clinical applications, such as adherence of strict regulations on cell isolation and expansion. Methods. In order to maintain GMP conformity, the automated cell processing system Sepax (Biosafe) was implemented for mononucleated cell (MNC) separation from fresh CB. After USSC generation, clinical-scale expansion was achieved by multi-layered CellSTACKs (Costar/Corning). Infectious disease markers, pyrogen and endotoxin levels, immunophenotype, potency, genetic stability and sterility of the cell product were evaluated. Results! . The MNC isolation and cell cultivation methods used led to safe and reproducible GMP-conforming USSC production while maintaining somatic stem cell character. Conclusions. Together with implemented in-process controls guaranteeing contamination-free products with adult stem cell character, USSC produced as suggested here may serve as a universal allogeneic stem cell source for future cell treatment and clinical settings. PMID: 20370349 [PubMed - in process]   Severely damaged kidneys possess multipotent renoprotective stem cells. April 8, 2010 at 6:27 AM Severely damaged kidneys possess multipotent renoprotective stem cells. Cytotherapy. 2010 May;12(3):303-12 Authors: Gheisari Y, Nassiri SM, Arefian E, Ahmadbeigi N, Azadmanesh K, Jamali M, Jahanzad I, Zeinali S, Vasei M, Soleimani M Abstract Background aims. Tissue-specific stem cells are a promising target for kidney regeneration, because it has been shown that they play a primary role in kidney repair. Several methods have been developed for the isolation of stem/progenitor cells from healthy kidneys but the existence of these cells in chronically damaged kidneys has not been noticed so far. Methods. A mouse model of chronic kidney failure was developed by ligation of the left ureter for 5 months, and then isolation of stem cells from this tissue as well as normal kidneys was attempted. Results. We found that multipotent stem cells could be isolated from both types of tissue. In addition, the cells isolated from damaged kidneys showed potential for homing to the site of injury and a renoprotective effect in an animal model of cisplatin-induced nephropathy. Conclusions. These results show that multipotent renoprotective stem cells exist in severely damaged kidneys, which could be a target fo! r designing new therapies. PMID: 20370347 [PubMed - in process]   Hydrostatic pressure stimulation of human mesenchymal stem cells seeded on collagen-based artificial extracellular matrices. April 8, 2010 at 6:27 AM Hydrostatic pressure stimulation of human mesenchymal stem cells seeded on collagen-based artificial extracellular matrices. J Biomech Eng. 2010 Feb;132(2):021001 Authors: Hess R, Douglas T, Myers KA, Rentsch B, Rentsch C, Worch H, Shrive NG, Hart DA, Scharnweber D Human mesenchymal stem cells (hMSCs) from bone marrow are considered a promising cell source for bone tissue engineering applications because of their ability to differentiate into cells of the osteoblastic lineage. Mechanical stimulation is able to promote osteogenic differentiation of hMSC; however, the use of hydrostatic pressure (HP) has not been well studied. Artificial extracellular matrices containing collagen and chondroitin sulfate (CS) have promoted the expression of an osteoblastic phenotype by hMSCs. However, there has been little research into the combined effects of biochemical stimulation by matrices and simultaneous mechanical stimulation. In this study, artificial extracellular matrices generated from collagen and/or CS were coated onto polycaprolactone-co-lactide substrates, seeded with hMSCs and subjected to cyclic HP at various time points during 21 days after cell seeding to investigate the effects of biochemical, mechanical, and combined bioc! hemical and mechanical stimulations. Cell differentiation was assessed by analyzing the expression of alkaline phosphatase (ALP) at the protein- and mRNA levels, as well as for calcium accumulation. The timing of HP stimulation affected hMSC proliferation and expression of ALP activity. HP stimulation after 6 days was most effective at promoting ALP activity. CS-containing matrices promoted the osteogenic differentiation of hMSCs. A combination of both CS-containing matrices and cyclic HP yields optimal effects on osteogenic differentiation of hMSCs on scaffolds compared with individual responses. PMID: 20370238 [PubMed - in process]   [Progress and prospect of synthetic biodegradable polymers for bone repair and reconstruction] April 8, 2010 at 6:27 AM [Progress and prospect of synthetic biodegradable polymers for bone repair and reconstruction] Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010 Mar;24(3):363-7 Authors: Zhao Z, Jiang D OBJECTIVE: To review the latest researches of synthetic biodegradable polymers for bone repair and reconstruction, to predict the progress of bone substitute materials and bone tissue engineering scaffolds in future. METHODS: The literature concerning synthetic biodegradable polymers as bone substitute materials or bone tissue engineering scaffolds was collected and discussed. RESULTS: Aliphatic polyester, polyanhydride, polyurethane and poly (amino acids) were the most extensively studied synthetic biodegradable polymers as bone substitutes and the scaffolds. Each polymer was of good biological safety and biocompatibility, and the degradation products were nontoxic to human body. The mechanical properties and degradation rate of the polymers could be adjusted by the type or number of the monomers and different synthetic methods. Therefore, the polymers with suitable mechanical strength and degradation rate could be produced according to the different requirements! for bone grafting. Preliminary studies in vivo showed their favorable capacity for bone repair. CONCLUSION: The synthetic biodegradable polymers, especially the copolymers, composite materials and those carrying bone growth factors are expected to be the most promising and ideal biomaterials for bone repair and reconstruction. PMID: 20369542 [PubMed - in process]   [Cholestatic serum and hepatocyte growth factor induce differentiation of bone marrow mesenchymal stem cells into hepatocytes in vitro] April 8, 2010 at 6:27 AM [Cholestatic serum and hepatocyte growth factor induce differentiation of bone marrow mesenchymal stem cells into hepatocytes in vitro] Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010 Mar;24(3):344-9 Authors: Zhong X, Wan J, Wang Z, Hu L, Li C OBJECTIVE: To solve the shortage of hepatocytes for liver tissue engineering, to explore the possibility of proliferation of rat bone marrow mesenchymal stem cells (BMSCs) and the feasibility of differentiation of BMSCs into hepatocytes with a culture system containing cholestatic rat serum and hepatocyte growth factor (HGF) in vitro. METHODS: Myeloid cells of femur and tibia were collected from the female healthy Wistar rats at the age of 6 weeks, the BMSCs were isolated, purified and identified. Normal and cholestatic rat serum were prepared from 40 healthy Wistar rats at the age of 12-14 weeks. The 3rd passage of BMSCs were harvested and added different cultures according to the following grouping: group A, DMEM plus 10%FBS; group B, hepatocyte growth medium (HGM) plus 5%FBS; group C, HGM plus 5% normal rat serum; group D, HGM plus 5% cholestatic rat serum; group E, HGM plus 5% cholestatic rat serum plus 25 microg/L HGF. The changes of cell morphology were obse! rved, MTT assay was used to measure cell growth; the expression of alpha-fetoprotein (AFP) and cytokeratin 18 (CK18) were detected by immunocytochemistry; the glycogen deposit was examined by periodic acid-schiff (PAS) staining; and the urea content in culture supernatant was determined by glutamate dehydrogenase. RESULTS: Polygonal cells and binuclear cells were observed in groups D and E, while the shapes of cells in groups A, B, and C did not obviously change. The cell growth curve demonstrated that the speed of cells proliferation in group C was the fastest, the one in group B was the slowest; showing significant differences when compared with groups A, D, and E (P < 0.05). On the 7th day in groups D and E, the positive expressions of AFP and CK18 emerged, on the 14th day the positive expression of glycogen emerged. At the same period, the expression ratio was higher in group E than in group D (P < 0.05). The urea concentration increased gradually with induction t! ime in groups D and E, the concentration was higher in group E! than in group D (P < 0.05). No expressions of AFP, CK18, glycogen, and change of the urea concentration were observed in groups A, B, and C. CONCLUSION: Normal rat serum can obviously promote the growth of BMSCs; cholestatic rat serum which promote the growth of BMSCs can induce to differentiate into hepatocyte; and a combination of cholestatic serum and HGF can increase the differentiation ratio. PMID: 20369539 [PubMed - in process]   This email was sent to agupta1213+termsc@gmail.com.  Account Login Don't want to receive this feed any longer? Unsubscribe here This email was carefully delivered by Feed My Inbox. 230 Franklin Road Suite 814 Franklin, TN 37064